This invention relates to a means and a method for mounting motor vehicle wheels, especially wheels which are relatively thick in the hub region, often called "mag" wheels.
Conventional wheels furnished as original equipment on new passenger automobiles are usually made of pressed steel, having an axial thickness, in the vicinity of the hub, of about 1/4 inch. The wheel has a circumferentially spaced series of holes, usually four or five, for receiving threaded studs projecting out from the hub. Nuts, often called lug nuts, are screwed on the threaded studs and engage tightly with the wheel, holding the wheel in place relative to the hub.
Some motorists, especially racing car drivers, prefer not to use the customary original issue wheels, but to use special wheels which are much thicker (in an axial direction), especially in the vicinity of the hub, where the wheel may be 11/2 or 2 inches or more in thickness. To hold such wheels in place, extra long studs are used, projecting out (parallel to the axis of rotation) from the hub, to extend through the extra thickness of the wheel. The lug nuts have a cylindrical portion internally threaded to screw onto the stud and externally smooth to fit snugly in the hole extending through the thickness of the wheel, and a hexagonal or other non-circular portion to receive a wrench for tightening or loosening the nut, with a shoulder between the cylindrical or shank portion and the hex portion to bear against the wheel.
However, this usual arrangement for holding mag wheels in place on the hub is not entirely satisfactory. The length of the smooth cylindrical part of the lug nut must not extend all the way through the thickness of the wheel to the hub but must leave a gap between the inner end of the lug nut and the hub, in order that the nut will tighten against the wheel and not tighten against the hub before the wheel is clamped sufficiently tightly. Thus the wheel is unsupported at this critical point, next to the hub, where the gap is required. Moreover, although lug nuts come in different sizes, with cylindrical portions of different lengths, the longer ones are not only more expensive but also less common and harder to find in stock on the shelves of automotive supply stores, so there is a tendency of drivers to use shorter lug nuts, with the result that the gap between the inner end of the nut and the hub is often quite large, say 3/4 of an inch or 1 inch or more (with a wheel 2 inches thick), which is a very dangerous condition. With part of the thickness of the wheel unsupported by the studs, especially the part next to the hub, there is substantial risk of cracks and ultimate failure of the wheel in the vicinity of the unsupported area, especially at the high speeds of racing driving. Also, the vehicle weight transmitted to the wheel through the studs is applied at some distance outwardly from the hub, thus having a leverage effect which increases the bending stress to which each stud is subjected.
Moreover, it is hard to install the wheels, especially when attempted by one person alone without a helper. The wheel must be lifted up, have its holes aligned with the studs, then slipped over the studs, and if there is no helper to hold the wheel elevated while one or two nuts are screwed on at least partially, the wheel must be rested on the exposed threads of the studs while one reaches for the nuts and starts to screw them on, then the wheel must be slightly elevated to center the holes in the wheel with respect to the studs, so that the nuts may be screwed further onto the studs. Meanwhile, the temporary resting of the wheel on the studs may have damaged the threads of the studs. All in all, the mounting of the thick or "mag" wheel is quite a ticklish and troublesome job, especially when done by one person alone.
An object of the present invention is the provision of an improved and more satisfactory means and method for mounting thick or "mag" wheels of motor vehicles.
Another object is the provision of a mounting method and means by which a mag wheel may be easily mounted by a single person working without assistance, without danger of damage to the threads of the studs.
A further important object of the invention is the provision of an arrangement which gives full support to the wheel structure at the inner part of its thickness, to promote safety and reduce the risk of breakage, particularly at high speed driving.
A still further object is the provision of an improved mounting arrangement which is relatively inexpensive, and which may be used easily and rapidly.